Advances in percutaneous coronary intervention

Clinical Outcomes of Revascularization Strategies for Patients With MVD/LMCA Disease: A Systematic Review and Network Meta-Analysis

Hybrid coronary revascularization (HCR), a new minimally invasive procedure for patients requiring revascularization for multivessel coronary lesions, combines coronary artery bypass grafting (CABG) for left anterior descending (LAD) lesions and percutaneous coronary intervention (PCI) for non-LAD coronary lesions. However, available data related to outcomes comparing the 3 revascularization therapies is limited to small studies.We conducted a search in MEDLINE, EMBASE, and the Cochrane Library of Controlled Trials up to December 31, 2014, without language restriction. A total of 16 randomized trials (n=4858 patients) comparing HCR versus PCI or off-pump CABG (OPCAB) were included in this meta-analysis. The primary outcomes were major adverse cardiac and cerebrovascular events (MACCE), all-cause death, myocardial infarction (MI), cerebrovascular events (CVE), and target vessel revascularization (TVR). Odds ratios (OR) and 95% confidence intervals (CI) were calculated using random-effect and fixed-effect models. Ranking probabilities were used to calculate a summary numerical value: the surface under the cumulative ranking (SUCRA) curve.No significant differences were seen between the HCR and PCI in short term (in hospital and 30 days) with regard to MACCE (odds ratio [OR] = 0.51, 95% confidence interval [CI] 0.00-2.35), all-cause death (OR = 2.09, 95% CI 0.34-7.66), MI (OR = 1.02, 95% CI 0.19-2.95), CVE (OR = 4.45, 95% CI 0.39-19.16), and TVR (OR = 6.99, 95% CI 0.17-39.39). However, OPCAB had lower MACCE than HCR (OR = 0.19, 95% CI 0.00-0.95). In midterm (1 year and 3 year), in comparison with HCR, PCI had higher all-cause death (OR = 5.66, 95% CI 0.00-13.88) and CVE (OR = 4.40, 95% CI 0.01-5.68), and lower MI (OR = 0.51, 95% CI 0.00-2.86), TVR (OR = 0.53, 95% CI 0.05-2.26), and thus the MACCE (OR = 0.51, 95% CI 0.00-2.35). Off-pump CABG presented a better outcome than HCR with significant lower MACCE (OR = 0.17, 95% CI 0.01-0.68). Surface under the cumulative ranking probabilities showed that HCR may be the superior strategy for MVD and LMCA disease when regarded to MACCE (SUCRA = 0.84), MI (SUCRA = 0.76) in short term, and regarded to MACCE (SUCRA = 0.99), MI (SUCRA = 0.94), and CVE (SUCRA = 0.92) in midterm.Hybrid coronary revascularization seemed to be a feasible and acceptable option for treatment of LMCA disease and MVD. More powerful evidences are required to precisely evaluate risks and benefits of the 3 therapies for patients who have different clinical characteristics.

Optimum parameters for freeze-drying decellularized arterial scaffolds

Decellularized arterial scaffolds have achieved success in advancing toward clinical use as vascular grafts. However, concerns remain regarding long-term preservation and sterilization of these scaffolds. Freeze drying offers a means of overcoming these concerns. In this study, we investigated the effects of various freeze-drying protocols on decellularized porcine carotid arteries and consequently, determined the optimum parameters to fabricate a stable, preserved scaffold with unaltered mechanical properties. Freeze drying by constant slow cooling to two final temperatures ((Tf), -10 °C and -40 °C) versus instant freezing was investigated by histological examination and mechanical testing. Slow cooling to Tf= -10 °C produced a stiffer and less distensible response than the non freeze-dried scaffolds and resulted in disruption to the collagen fibers. The mechanical response of Tf= -40 °C scaffolds demonstrated disruption to the elastin network, which was confirmed with histology. Snap freezing scaffolds in liquid nitrogen and freeze drying to Tf= -40 °C with a precooled shelf at -60 °C produced scaffolds with unaltered mechanical properties and a histology resembling non-freeze-dried scaffolds. The results of this study demonstrate the importance of optimizing the nucleation and ice crystal growth/size to ensure homogenous drying, preventing extracellular matrix disruption and subsequent inferior mechanical properties. This new manufacturing protocol creates the means for the preservation and sterilization of decellularized arterial scaffolds while simultaneously maintaining the mechanical properties of the tissue.